Superabsorbent water sensitive multilayer construction

ABSTRACT

A multilayer construction that includes a first layer that includes water sensitive thermoplastic polymer and a second layer disposed on the first layer, the second layer including superabsorbent polymer.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. Patent Application Ser. No.10/121,171 filed Apr. 11, 2002, now U.S. Pat. No. ______, andincorporated herein.

BACKGROUND

The invention is directed to a superabsorbent multilayer construction.

Superabsorbent polymers, which are available as powders, particles, andaqueous compositions, absorb large quantities of water and are oftenused in absorbent articles to increase the absorbency of the article.Disposable diapers and feminine hygiene products often includesuperabsorbent polymers to enhance body fluid absorption. Superabsorbentpolymers also have various applications in the medical, food, andagricultural industries.

SUMMARY

In one aspect, the invention features a multilayer construction thatincludes a first layer including water sensitive thermoplastic polymer,and a second layer disposed on the first layer, the second layerincluding superabsorbent polymer. In one embodiment, the thermoplasticpolymer includes polyamide. In another embodiment the thermoplasticpolymer includes the reaction product of polyoxyalkylene glycol diamineand an acid selected from the group consisting of dicarboxylic acid,dicarboxylic acid ester, and combinations thereof, the polyoxyalkyleneglycol diamine having the formulaNH₂—(CH₂)_(x)—(OCH₂—CH₂)_(y)—O—(CH₂)_(x)—NH₂, where 2≦X≦3, and 1≦Y≦2. Inother embodiments, the thermoplastic polymer includes the reactionproduct of adipic acid and polyoxyalkylene glycol diamine. In anotherembodiment, the thermoplastic polymer is water soluble.

In some embodiments, the superabsorbent polymer includes crosslinkedpolyacrylate. In other embodiments, the superabsorbent polymer includescrosslinked and at least partially neutralized α,β-beta ethylenicallyunsaturated monomers selected from the group consisting ofmonocarboxylic acid monomers, dicarboxylic acid monomers, acid anhydridemonomers, and combinations thereof.

In one embodiment, the construction exhibits an absorption rate greaterthan the absorption rate of the superabsorbent polymer layer in theabsence of the thermoplastic layer.

In other embodiments, an above-described multilayer construction is afilm. In one embodiment the film exhibits an absorption rate greaterthan the absorption rate of the superabsorbent polymer layer in theabsence of the thermoplastic layer. In some embodiments, the film isflexible.

In some embodiments, an above-described multilayer construction is afiber.

In another aspect, the invention features an article that includes anonwoven web and an above-described multilayer construction disposed onthe web.

In some aspects, the invention features a multi-component fiber thatincludes a first component that includes water sensitive thermoplasticpolymer, and a second component that includes superabsorbent polymer,the second component being disposed on the first component. In oneembodiment, the first component includes a core and the second componentincludes a sheath.

In other aspects the invention features a multi-component yarn thatincludes a first component that includes water sensitive thermoplasticpolymer, and a second component comprising superabsorbent polymer, thesecond component being disposed on the first component. In someembodiments, the first component includes a core that includes the watersensitive thermoplastic polymer. In another embodiment, the secondcomponent includes a sheath that includes the superabsorbent polymer.

In another embodiment, a disposable article (e.g., a diaper) includes anabove-described multilayer construction.

In another aspect, the invention features a method of making amultilayer construction that includes coating an aqueous water solublesuperabsorbent polymer composition on a water sensitive thermoplasticfilm.

In one embodiment, the method includes providing a molten watersensitive thermoplastic polymer, and contacting the molten thermoplasticpolymer with an aqueous water soluble superabsorbent polymercomposition. In another embodiment, the molten thermoplastic polymer isin a form selected from the group consisting of fibers, filaments andcombinations thereof. In some embodiments, the molten thermoplasticpolymer is in the form of a film.

The invention features a superabsorbent self-supporting film that iscapable of degrading in water, is flushable, and degrades in a sewersystem. The multiplayer construction and can also be constructed toinclude a water soluble thermoplastic polymer layer and be capable ofdissolving in water. The invention also features a multilayerconstruction that can be disposed on a substrate or incorporated into anarticle to render the article water soluble, water swellable, waterdispersible or a combination thereof.

The multilayer construction is well suited to use in personal hygieneproducts and can be incorporated into such products to render theproducts more able to degrade in sewer and waste disposal systems.

The multilayer construction can be constructed to be thermally bonded toa substrate.

The multilayer construction, when in the form of a continuous ordiscontinuous film can allow liquid to pass through the layers of theconstruction to a second layer, e.g., an absorbent core, where it canthen be stored. Storage of the liquid in the second layer allows theliquid to be maintained away from the skin of the user.

GLOSSARY

In reference to the invention, these terms have the meanings set forthbelow:

“Water sensitive” means water soluble, water dispersible, waterswellable, and combinations thereof.

Other features and advantages will be apparent from the followingdescription of the preferred embodiments and from the claims.

DETAILED DESCRIPTION

The multilayer construction (e.g., film) includes a layer ofsuperabsorbent polymer disposed on a layer of water sensitivethermoplastic polymer. When the superabsorbent layer of the multilayerconstruction is contacted with an aqueous composition it forms a gel andthe thermoplastic layer at the interface with the gelling superabsorbentlayer substantially maintains its integrity as the superabsorbent layergels. The multilayer construction can be constructed to gel at a ratefaster than the gel rate that would be exhibited by the superabsorbentpolymer layer in the absence of the water sensitive thermoplastic layer.

The superabsorbent layer includes superabsorbent polymer preferably inthe form of a continuous or discontinuous coating or film. Thesuperabsorbent polymer absorbs many times its own weight in water,preferably at least 50 times, more preferably at least 100 times, mostpreferably at least 150 times its weight in water. The ability of thesuperabsorbent polymer to absorb water is related to the degree ofcrosslinking present in the superabsorbent polymer. Increasing thedegree of crosslinking increases the superabsorbent polymer's totalfluid holding capacity under load. The degree of crosslinking ispreferably optimized to obtain a composition in which the rate andamount of absorbency are optimized. Preferred superabsorbent polymersare at least 10%, more preferably from about 10% to about 50%, mostpreferably from about 20% to 40% crosslinked. Examples of suitablesuperabsorbent polymers include crosslinked and polymerized α,β-betaethylenically unsaturated mono- and dicarboxylic acids and acidanhydride monomers including, e.g., acrylic acid, methacrylic acid,crotonic acid, maleic acid/anhydride, itaconic acid, fumaric acid, andcombinations thereof.

The superabsorbent layer is preferably formed from an aqueouscomposition of water soluble superabsorbent polymer (i.e., a polymerthat exhibits superabsorbent properties when crosslinked), andcrosslinking agent. The aqueous superabsorbent polymer compositionexhibits a pH of from about 7 to about 10, preferably a pH greater than7, which can be achieved by adding a pH adjusting agent (e.g., a base)to the aqueous superabsorbent polymer composition. Examples of useful pHadjusting agents include alkali metal hydroxide (e.g., sodium hydroxideand potassium hydroxide), alkali metal alkoxide, alkaline earth metalhydroxide (e.g., calcium hydroxide), and combinations thereof. The pHadjusting agent assists in neutralizing the acid groups of the watersoluble superabsorbent polymer. Preferably alkali metal hydroxide oralkaline earth metal hydroxide is added to neutralize from about 50% toabout 95% of the carboxyl groups, preferably from greater than 65% toabout 95% of the carboxyl groups, more preferably from about 70% toabout 95% of the carboxyl groups, more preferably from about 70% toabout 85% of the carboxyl groups, most preferably about 75% of thecarboxyl groups. The water soluble superabsorbent polymer is thenfurther neutralized (e.g., at least 100% neutralized) with a volatilebase. The volatile base dissipates from the aqueous water solublesuperabsorbent polymer composition as the composition dries, whichallows the crosslinking agent to crosslink the water solublesuperabsorbent polymer to form a high molecular weight polymer, i.e.,the superabsorbent polymer. Examples of suitable volatile bases includeammonia, e.g., ammonium hydroxide, amines including, e.g., methylamineand dimethylamine, and combinations thereof.

The viscosity of the aqueous water soluble superabsorbent polymercomposition is selected to facilitate application of the composition ona substrate (e.g., the water soluble thermoplastic polymer component).Useful aqueous water soluble superabsorbent polymer compositions have aviscosity of from about 50 cPs to about 50,000 cPs, more preferably, inincreasing order of preference, from about 100 cPs to about 30,000 cPs,from abut 100 cPs to about 20,000 cPs, from about 100 cPs to abut 10,000cPs, from about 100 cPs to about 5000 cPs, from about 100 cPs to abut2500 cPs at room temperature (i.e., 25° C.) for a 20% by weight solidscomposition. Preferably the water soluble superabsorbent polymer has amolecular weight of from about 9000 Mw to about 4,000,000 Mw, morepreferably from about 20,000 Mw to about 1,000,000 Mw, most preferablyfrom about 100,000 Mw to about 200,000 Mw.

The aqueous water soluble superabsorbent polymer composition includesfrom 5% by weight to about 65% by weight, preferably from about 10% byweight to about 50% by weight, more preferably from about 20% by weightto about 40% by weight solids.

The crosslinking agent is selected to complex with the functionalhydrophilic groups of the water soluble superabsorbent polymer.Preferred crosslinking agents complex with the functional groups on thewater soluble superabsorbent polymer once the water phase of the polymercomposition has dissipated. Useful crosslinking agents include, e.g.,di- and trivalent crosslinking salts including, e.g., zirconium salts,zinc salts, chromium salts, and combinations thereof, zirconium ions,which can be mixed with ferric aluminum ions, chromic ions, titaniumions, and aziridine, and combinations thereof. Other useful crosslinkingagents are described in U.S. Pat. No. 4,090,013 and incorporated herein.Useful commercially available crosslinking agents include ammoniumzirconyl carbonate available under the trade designations BACOTE 20 andZIRMEL 1000 from Magnesium Elektron, Inc. (Flemington, N.J.), andaziridine crosslinking agents available under the trade designationNEOCRYL CX-100 from Zeneca Resins (Wilmington, Mass.). Preferably thecrosslinking agent is added to the aqueous superabsorbent prepolymercomposition in an amount of from about 2 parts to about 10 parts,preferably from about 2 parts to about 8 parts, most preferably fromabout 4 parts to 6 parts.

The crosslinking agent can also be provided separately from the aqueouswater soluble superabsorbent polymer composition. In some applications,the aqueous water soluble superabsorbent polymer composition is appliedto the water sensitive thermoplastic layer prior to or after applicationof the crosslinking agent in a two-step process. When the aqueous watersoluble superabsorbent polymer and crosslinking agent are appliedseparately, the aqueous water soluble superabsorbent polymer compositionis preferably dried prior to contact with the crosslinking agent.

Preferred superabsorbent polymers are capable of being hydroplasticizedby ambient moisture. The hydroplasticized superabsorbent polymerprovides a pliant film exhibiting extensibility and flexibility.Preferably the superabsorbent polymer absorbs moisture from the air atambient temperature and 50% relative humidity in an amount of at leastabout 5% by weight, more preferably at least about 10% by weight, mostpreferably at least about 20% by weight of the anhydrous superabsorbentpolymer.

The aqueous water soluble superabsorbent polymer composition may alsoinclude small amounts of water soluble monomers including, e.g.,2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, vinyl pyrrolidone,acrylamide, methacrylamide, sodium vinyl sulfonated, and1-allyloxy-2-hydroxypropane sulfonate.

Useful water sensitive thermoplastic polymers include water solublethermoplastic polymers, water dispersible thermoplastic polymers andwater swellable thermoplastic polymers. Suitable water sensitivethermoplastic polymers include crystalline water sensitive thermoplasticpolymers and amorphous water sensitive thermoplastic polymers. The term“crystalline polymer” means those polymers that retain their rubberyelastomeric or flexible properties above the glass transition, until themelting temperature has been surpassed. Melting of the crystallinepolymer is also accompanied by a loss of crystalline X-ray diffractioneffects. An “amorphous polymer” is a polymer that, with increasingtemperature, passes from a solid phase to a liquid phase without adiscernible transition point.

Suitable water soluble crystalline thermoplastic polymers include thereaction product of a polyoxyalkylene glycol diamine or apolyoxyalkylene glycol amine, and a dicarboxylic acid or dicarboxylicacid ester. Preferred polyoxyalkylene glycol diamines have the formula:NH₂—(CH₂)_(x)—(OCH₂—CH₂)_(y)—O—(CH₂)_(x)—NH₂where 2≦X≦3, and 1≦Y≦2. Examples of suitable polyoxyalkylene glycoldiamines include triethylene glycol diamine, wherein X=2 and Y=1, andtetraethylene glycol diamine, wherein 2≦X≦3 and Y=2. Useful commerciallyavailable polyoxyalkylene glycol diamines are available under the tradedesignations JEFFAMINE XTJ-504 and JEFFAMINE EDR-192 (tetraethyleneglycol diamine) from Huntsman Chemical Co. (Houston, Tex.). A preferreddiamine is 4,7,10-trioxatridecane-1,13-diamine (TTD diamine) where X=3and Y=2, which is available from BASF (Parsippany, N.J.).

Useful polyoxyalkylene glycol amines include JEFFAMINE D-230, D-400,XTJ-500, XTJ-501, and XTJ-502 provided a chain terminator acid or amineis employed during the reaction, and/or additional ingredients such aswaxes, tackifiers, crystalline polymers, and monoacids are subsequentlycombined with the reacted polyamide When adipic acid is reacted withtrioxytridecane-1,13-diamine and JEFFAMINE D-230, for example, theresulting polyamide is relatively slow setting relative to the reactionof adipic acid and trioxytridecane-1,13-diamine alone. Thepolyoxyalkylene glycol diamine is reacted with an equal stoichiometricratio of a dicarboxylic acid.

Suitable dicarboxylic acids include those dicarboxylic acids having from5 to 36 carbon atoms including, e.g., adipic acid, pimelic acid, azelaicacid, sebacic acid, suberic acid, dodecanedioic acid, terephthalic acid,isophthalic acid, t-butyl isophthalic acid, dimer acid, and mixturesthereof. The esters and anhydrides of these acids may also be used.

Particularly useful water soluble polyether amides have a melting pointno greater than 190° C. and include, e.g., the reaction products ofadipic acid and JEFFAMINE XTJ-504, adipic acid and JEFFAMINE EDR-192,and adipic acid and TTD diamine.

Suitable crystalline water soluble polyamides are commercially availableunder the trade designations NP-2126, NP-2110, NP-2116, and NP-2068 fromH.B. Fuller Company (St. Paul, Minn.).

Suitable crystalline water dispersible polymers include, e.g.,polyethylene oxide available, e.g., from Union Carbide (Danbury, Conn.)and crystalline polyesters.

Suitable amorphous water sensitive thermoplastic polymers include, e.g.,polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl pyrrolidone/vinylacetate, polyvinyl pyrrolidone/acrylic acid, polyetheroxazoline, andlinear and branched water dispersible polyesters.

Suitable commercially available amorphous water dispersiblethermoplastic polymers include, e.g., polyvinyl alcohol available underthe trade designations GROHSERAN L-301 and GROHSERAN L-302 from NipponGroshei (Japan), and under the trade designation UNITIKA from UnitakaLtd. (Japan); polyvinyl pyrrolidone available from BASF (Mount Olive,N.J.), and International Specialty Products (Wayne, N.J.); polyvinylpyrrolidone/vinyl acetate copolymer and polyvinyl pyrrolidone/acrylicacid available under the trade designation ACRYLIDONE, both of which areavailable from ISP; polyethyloxazoline available under the tradedesignation PEOX from The Dow Chemical Company (Freeport, Tex.), andunder the trade designation AQUAZOL from PCI Incorporated (Tucson,Ariz.), polyvinyl methyl ether available under the trade designationAMOBOND from Amoco Chemical Co., linear polyesters, polyacrylamide, andwater dispersible polyesters and copolyesters available under the tradedesignation EASTMAN AQ including EASTMAN AQ-14000, EASTMAN AQ-1950, andEASTMAN AQ-1045 from Eastman Chemical Company (Kingsport, Tenn.).

Suitable water dispersible polyesters and copolyesters are availableunder the EASTMAN AQ trade designation and include linear polyesters orbranched sulfonated copolyesters. Such polymers are saline and bodyfluid insoluble, yet dispersible in tap water. The Tg of the branchedwater dispersible copolyesters ranges from about −5° C. to 7° C.,whereas the linear polyesters have a Tg from about 30° C. to about 60°C. Linear thermoplastic water dispersible polyesters are commerciallyavailable under the EASTMAN AQ series of trade designations including,e.g., EASTMAN AQ 35S (7,000 Mn), AQ 38S (10,000 Mw), and AQ 55S (8,000Mn) all from Eastman Chemical Company (Kingsport, Tenn.). Branchedthermoplastic water dispersible polyesters are commercially availableunder the EASTMAN AQ series of trade designations including, e.g.,EASTMAN AQ 1045, AQ 1350, AQ 1950, and AQ 14000 from Eastman ChemicalCompany.

Other useful water sensitive polymers are commercially available underthe Hydromelt trade designation from H.B. Fuller Company (St. Paul,Minn.) and include NP 2116, NP 2055, NP 2068, and NP 2110.

Useful water sensitive thermoplastic polymers and their methods ofmanufacture are disclosed, e.g., in U.S. Pat. No. 3,882,090 (Fagerberget al.), U.S. Pat. No. 5,053,484 (Speranza et al.), U.S. Pat. No.5,118,785 (Speranza et al.), U.S. Pat. No. 5,086,162 (Speranza et al.),U.S. Pat. No. 5,324,812 (Speranza et al.), U.S. Pat. No. 5,899,675(Ahmed et al.), U.S. Pat. No. 5,863,979 (Ahmed et al.), U.S. Pat. No.5,663,286 (Ahmed et al.), and U.S. Pat. No. 5,869,596 (Ahmed et al.),and incorporated herein.

The water soluble thermoplastic polymer layer can also include additivesincluding, e.g., waxes, tackifying resins, crystalline polymers,monocarboxylic acids, and mixtures thereof as well as monocarboxylicacids and monoamines.

Preferably the multilayer construction is oriented such that thesuperabsorbent polymer layer is exposed to a fluid to be absorbed, e.g.,water, body fluid, and combinations thereof.

The multilayer construction can exist in a variety of forms including,e.g., fibers (e.g., a multicomponent fiber, e.g., core-sheathconstruction), yarn (e.g., multicomponent yarn), film (e.g., afreestanding film), a coating on a substrate (including, e.g., woven andnonwoven substrates, porous substrates, films, fibers, and yarns), andcombinations thereof. The multilayer construction, itself, as well asthe layers of the multilayer construction can be continuous ordiscontinuous including, e.g., striped, dotted, and patterned.

The multilayer construction can be free standing (e.g., a film, fiber,and yarn) or associated with, e.g., disposed on, a substrate including,e.g., fibers, yarns, webs (woven and nonwoven), films, release liners,and combinations thereof. Useful fibers include cellulose fibersincluding, e.g., wood pulp, cotton, silk, and wool, and synthetic fibersincluding, e.g., nylon, rayon, polyesters, acrylics, polypropylenes,polyethylene, polyvinyl chloride, polyurethane, glass, and combinationsthereof. The multilayer construction can be disposed on the substrate invarious forms including, e.g., continuous and discontinuous (e.g.,striped, dotted, and patterned) coatings, laminates, and combinationsthereof.

The layers of the construction can be applied to or formed on thesubstrate simultaneously or sequentially using a variety of techniquesincluding, e.g., immersing, soaking, impregnating, spraying, extruding(e.g., coextrusion), laminating, coating (e.g., dip coating, slot,gravure, knife, and contact coating), and combinations thereof. Poroussubstrates, for example, can be sequentially impregnated with theaqueous superabsorbent polymer and the water sensitive thermoplasticpolymer.

Preferably the aqueous water soluble superabsorbent polymer compositionis applied to the water sensitive component of the construction whilethe water sensitive thermoplastic component is at a higher temperature,e.g., in a molten state or a temperature in the melt temperature rangeof the water sensitive thermoplastic polymer, relative to the aqueoussuperabsorbent polymer composition. In the case where the watersensitive component is formed by extrusion, for example, the aqueouswater soluble superabsorbent polymer composition can be applied to thewater sensitive component as it is extruded, and, in the case of fibersand filaments, the aqueous water soluble superabsorbent polymercomposition can be applied to the fibers or filaments at or near thepoint at which the fibers or filaments are released from the fiber orfilament forming orifice. The relatively higher temperature exhibited bythe water sensitive thermoplastic component as it is extruded from anorifice increases the rate of dissipation of the aqueous component ofthe aqueous water soluble superabsorbent polymer composition appliedthereto.

The multilayer construction is suitable for use in a variety of articlesincluding, e.g., absorbent articles such as diapers, sanitary napkins,bandages, wound care products, surgical pads, drapes, and gowns as wellas various paper products such as paper towels, toilet paper, and facialtissue, cable wrap, and packaging.

One useful article includes a fibrous nonwoven web and the multilayerconstruction disposed on the web. The multilayer construction caninclude perforations to allow liquid to pass through the construction toa second layer, e.g., a nonwoven web.

The multilayer construction also can be incorporated into an absorbentarticle that includes, e.g., a body fluid pervious top sheet, anacquisition layer, an absorbent layer (e.g., a fibrous core), a bodyfluid impermeable back sheet, and combinations thereof. The acquisitionlayer preferably is capable of dispersing liquid to the surface of theabsorbent layer. The absorbent layer may include loose fibers, fibersheld together through a binder, compressed fibers, and combinationsthereof. The fibers of the absorbent layer may be natural fibers (e.g.,wood pulp, jute, cotton, silk, and wool, and combinations thereof),synthetic fibers including (e.g., nylon, rayon polyester, acrylics,polypropylenes, polyethylene, polyvinyl chloride, polyurethane, andcombinations thereof), and combinations thereof. The multilayerconstruction can be in the form of a layer disposed between any of thecomponents.

In one absorbent article, the multilayer construction is perforated anddisposed between the wearer of the absorbent article and an absorbentlayer such that the thermoplastic layer is the first layer of themultilayer construction that is available for contact with a liquid. Theperforations allow a liquid to pass through the multilayer constructionfrom the thermoplastic layer to the superabsorbent layer. Thesuperabsorbent layer then gels upon contact with the water and theabsorbent layer of the absorbent article absorbs the water.

The invention will now be described by way of the following examples.All ratios and percentages are by weight unless otherwise indicated.

EXAMPLES Example

FULATEX PD8081H aqueous polyacrylic acid solution polymer and ammoniumzirconyl carbonate composition (H.B. Fuller Company, St. Paul, Minn.)was coated onto a 50 um thick NP 2116 polyamide film (H.B. FullerCompany) and dried to form a film construction that included a 15 umsuperabsorbent polymer coating on the 50 um polyamide film.

Water droplets were dropped onto the superabsorbent polymer surface ofthe film construction using an eye dropper. The treated film wasobserved. The water was rapidly adsorbed and then absorbed by thesuperabsorbent polymer and formed a gel in five seconds. The water wasthen absorbed by the thermoplastic layer of the film construction. Afterthree minutes the film construction had dissolved in the location of thewater droplets.

Other features are present in the claims.

1. A multilayer construction comprising: a first layer comprising watersensitive thermoplastic polymer; and a second layer comprisingsuperabsorbent polymer, said second layer being disposed on said firstlayer.
 2. The multilayer construction of claim 1, wherein saidthermoplastic polymer comprises polyamide.
 3. The multilayerconstruction of claim 1, wherein said water sensitive thermoplasticpolymer comprises the reaction product of polyoxyalkylene glycol diamineand an acid selected from the group consisting of dicarboxylic acid,dicarboxylic acid ester and combinations thereof, said polyoxyalkyleneglycol diamine having the formulaNH₂—(CH₂)_(x)—(OCH₂—CH₂)_(y)—O—(CH₂)_(x)—NH₂, where 2≦X≦3, and 1≦Y≦2. 4.The multilayer construction of claim 1, wherein said water sensitivethermoplastic polymer comprises the reaction product of adipic acid andpolyoxyalkylene glycol diamine.
 5. The multilayer construction of claim1, wherein said water sensitive thermoplastic polymer is water soluble.6. The multilayer construction of claim 1, wherein said superabsorbentpolymer comprises crosslinked polyacrylate.
 7. The multilayerconstruction of claim 1, wherein said superabsorbent polymer comprisescrosslinked and at least partially neutralized α,β-beta ethylenicallyunsaturated monomers selected from the group consisting ofmonocarboxylic acid monomers, dicarboxylic acid monomers, acid anhydridemonomers and combinations thereof.
 8. The multilayer construction ofclaim 1, wherein said construction exhibits an absorption rate greaterthan the absorption rate of the superabsorbent polymer layer in theabsence of said thermoplastic layer.
 9. The multilayer construction ofclaim 1, further comprising perforations.
 10. A film comprising themultilayer construction of claim
 1. 11. The film of claim 10, whereinsaid film exhibits an absorption rate greater than the absorption rateof the superabsorbent polymer layer in the absence of said thermoplasticlayer.
 12. The film of claim 10, further comprising perforations.
 13. Afilm comprising the multilayer construction of claim
 3. 14. A filmcomprising the multilayer construction of claim
 6. 15. A fibercomprising the multilayer construction of claim
 1. 16. A fibercomprising the multilayer construction of claim
 3. 17. A fibercomprising the multilayer construction of claim
 6. 18. An articlecomprising: a nonwoven web; and a multilayer construction disposed onsaid web, said multilayer construction comprising a first layercomprising a water sensitive thermoplastic polymer; and a second layercomprising a superabsorbent polymer, said second layer being disposed onsaid first layer.
 19. An article comprising: an absorbent layer; and afilm comprising a first layer comprising a water sensitive thermoplasticpolymer, and a second layer comprising a superabsorbent polymer, saidsecond layer being disposed on said first layer.
 20. A multi-componentfiber comprising: a first component comprising water sensitivethermoplastic polymer; and a second component comprising superabsorbentpolymer, said second component being disposed on said first component.21. The multi-component fiber of claim 20, wherein said first componentcomprises a core and said second component comprises a sheath.
 22. Amulti-component yarn comprising: a first component comprising watersensitive thermoplastic polymer; and a second component comprisingsuperabsorbent polymer, said second component being disposed on saidfirst component.
 23. The multi-component yarn of claim 22, wherein saidfirst component comprises a core comprising the water sensitivethermoplastic polymer.
 24. The multi-component yarn of claim 22, whereinthe second component comprises a sheath comprising the superabsorbentpolymer.
 25. A disposable article comprising the multilayer constructionof claim
 1. 26. A diaper comprising the multilayer construction of claim1.